Features:1. High high quality workplace chair caster wheel.2. Universally match all office chair bases with mounting holes.3. Twin wheel design enhances weight distribution and soft operation, ease to drift and swivel.4. Swivel and roll freely and more quietly in each path while not having for maintenance.4. Easy match - Just click on in Specifications:Material: Steel and Plastic Wheel diameter: Approx 50mm (2 inch)Stem Length: Approx 21mmStem Diameter: Approx 11mmGrip Ring Type (Look on the picture)Color: White / Gray Package Includes:5 x Chair Wheels